Question

Which point would map onto itself after a reflection across the line y= -x

A) -4,-4
B) -4,0
C) 0,-4
D) 4,-4

Answer 1

D. (4, -4).

Explanation:

y = -x is a line that has a negative slope of -1 ( rising to the left) and passing through the origin. It makes an angle of 45 degrees with the x-axis.

So, for example the point ( 0,1 )will map onto( -1 , 0).

Any point which maps on to itself across this line will have to lie on the line.

If x = 4 y = -x = -4.

Answer 2

d

Explanation: